Library classification - New World Encyclopedia Library classification Next (Library of Congress) A library classification is a system of coding and organizing library materials ( books , serials, audiovisual materials, computer files, maps , manuscripts , realia) according to their subject and allocating a call number to that information resource. Similar to classification systems used in biology, bibliographic classification systems group entities that are similar together typically arranged in a hierarchical tree structure (assuming none-faceted system). Library classification forms part of the field of library and information science. It goes hand in hand with library (descriptive) cataloging under the rubric of cataloging and classification, sometimes grouped together as technical services. The library professional who engages in the process of cataloging and classifying library materials is called a cataloger or catalog librarian. Library classification systems are one of the two tools used to facilitate subject access. The other are alphabetical indexing languages such as Thesaurui and Subject Headings systems. Contents In the United States, academic libraries generally use the Library of Congress classification system and public and school libraries use the Dewey Decimal Classification System. Overview Classification of a piece of work consists of two steps. Firstly the 'aboutness' of the material is ascertained.

Next, a call number based on the classification system will be assigned to the work using the notation of the system. It is important to note that unlike subject heading or Thesaurui where multiple terms can be assigned to the same work, in classification systems, each work can only be placed in one class. This is true also for faceted (see later) classification systems due to the enforcement of a citation order. Most classification systems like DDC and Library of Congress classification, also add a "cutter number" to each work which adds a code for the author of the work. Classification systems in libraries generally play two roles. Firstly, they facilitate subject access by allowing the user to find out what works or documents the library has on a certain subject. Secondly, they provide a known location for the information source to be located (e.g where it is shelved). Until the nineteenth century, most libraries had closed stacks, so the library classification only served to organize the subject catalog . In the twentieth century, libraries opened their stacks to the public and started to shelve the library material itself according to some library classification to simplify subject browsing. Some classification systems are more suitable for aiding subject access, rather than for shelf location.

For example, UDC which uses a complicated notation including plus, colons are more difficult to use for the purpose of shelf arrangement but are more expressive compared to DDC in terms of showing relationships between subjects. Similarly faceted classification schemes are more difficult to use for shelf arrangement, unless the user has knowledge of the citation order. Depending on the size of the library collection, some libraries might use classification systems solely for one purpose or the other. In extreme cases a public library with a small collection might just use a classification system for location of resources but might not use a complicated subject classification system. Instead all resources might just be put into a couple of wide classes (Travel, Crime, Magazines etc). This is known as a "mark and park" classification method. In the United States, academic libraries generally use Library of Congress classification system and public and school libraries use Dewey Decimal Classification System. Types There are many standard systems of library classification in use, and many more have been proposed over the years. However in general, Classification systems can be divided into three types depending on how they are used. Universal schemes covering all subjects. Examples include Dewey Decimal Classification and Library of Congress Classification Specific classification schemes.

Examples includes Iconclass, British classification of Music National schemes specially created for certain countries. Example is SAB. In terms of functionality, classification systems are often described as enumerative: produce an alphabetical list of subject headings, assign numbers to each heading in alphabetical order hierarchical: divides subjects hierarchically, from most general to most specific faceted or analytico-synthetic: divides subjects into mutually exclusive orthogonal facets There are few completely enumerative systems or faceted systems, most systems are a blend but favouring one type or the other. The most common classification systems, LCC and DDC, are essentially enumerative, though with some hierarchical and faceted elements (more so for DDC), especially at the broadest and most general level. The first true faceted system was the Colon classification of S. R. Ranganathan. Specific classification systems used in English-speaking world Bliss bibliographic classification (BC) Universal Decimal Classification Brinkler classification Newer classification systems tend to use the principle of synthesis (combining codes from different lists to represent the different attributes of a work) heavily, which is comparatively lacking in LC or DDC.

Comparing Classification Systems As a result of differences in Notation, history, use of enumeration, hierarchy , facets, classification systems can differ in the following ways Type of Notation - Notation can be pure (consisting of only numerals for example) or mixed (consisting of both alphabets and numerals or other symbols). Expressiveness - This is the degree in which the notation can express relationship between concepts or structure. Whether they support mnemonics - For example the number 44 in DDC notation usually means it concerns some aspect of France. For example 598.0944 concerns "Birds in France." The 09 signifies country code, and 44 represents France. Hospitality - The degree in which the system is able to accommodates new subjects Brevity - Length of the notation to express the same concept Speed of updates and degree of support - The best classification systems are constantly being reviewed and improved. Consistency Library of Congress Classification System Library of Congress reading room The Library of Congress Classification (LCC) is a system of library classification developed by the Library of Congress . It is used by most research and academic libraries in the U.S.

and several other countries—most public libraries and small academic libraries continue to use the Dewey Decimal Classification (DDC). It is not to be confused with the Library of Congress Subject Headings or Library of Congress Control Number. The classification was originally developed by Herbert Putnam with the advice of Charles Ammi Cutter in 1897 before he assumed the librarianship of Congress. It was influenced by Cutter Expansive Classification, DDC, and was designed for the use by the Library of Congress. The new system replaced a fixed location system developed by Thomas Jefferson . By the time of Putnam's departure from his post in 1939 all the classes except K (Law) and parts of B (Philosophy and Religion) were well developed. It has been criticized as lacking a sound theoretical basis; many of the classification decisions were driven by the particular practical needs of that library, rather than considerations of epistemological elegance. Although it divides subjects into broad categories, it is essentially enumerative in nature. It provides a guide to the books actually in the library, not a classification of the world. The National Library of Medicine classification system (NLM) uses unused letters W and QS-QZ.

Some libraries use NLM in conjunction with LCC, eschewing LCC's R (Medicine). The system Bibliography, Library Science, and General Information Resources Library of Congress Subject Headings The Library of Congress Subject Headings (LCSH) comprise a thesaurus (in the information technology sense) of subject headings, maintained by the United States Library of Congress , for use in bibliographic records. LC Subject Headings are an integral part of bibliographic control, which is the function by which libraries collect, organize and disseminate documents. LCSHs are applied to every item within a library’s collection, and facilitate a user’s access to items in the catalogue that pertain to similar subject matter. If users could only locate items by ‘title’ or other descriptive fields, such as ‘author’ or ‘publisher’, they would have to expend an enormous amount of time searching for items of related subject matter, and undoubtedly miss locating many items because of the ineffective and inefficient search capability. An art and science Subject heading classification is a human and intellectual endeavor, where trained professionals apply topic descriptions to items in their collections. Naturally, every library may choose to categorize the subject matter of their items differently, without a uniform agreed upon standard.

The widespread use and acceptance of the Library of Congress Subject Headings facilitates the uniform access and retrieval of items in any library in the world using the same search strategy and LCSH thesaurus , if the correct headings have been applied to the item by the library. Thusly, LCSH decisions involve a great amount of debate and even controversy in the library community. Despite LCSH's wide-ranging and comprehensive scope, there are libraries where the use of LCSH is not ideal or effective. To deal with these types of collections and user communities, other subject headings may be required. The United States National Library of Medicine developed Medical Subject Headings (MeSH) to use on its many health science databases and collection. Many university libraries may apply both LCSH and MeSH headings to items. In Canada, the National Library of Canada worked with LCSH representatives to create a complementary set of Canadian Subject Headings (CSH) to access and express the topic content of documents on Canada and Canadian topics. LCSH policy issues Historically, issues have revolved around the terms employed to describe racial or ethnic groups. Notable has been the terms used to describe African-Americans .

Until the 1990s, the LCSH administrators had a strict policy of not changing terms for a subject category. This was enforced to tighten and eliminate the duplication or confusion that might arise if subject headings were changed. Therefore, one term to describe African-American topics in LCSH was ‘Afro-American’ long after that term lost currency and acceptance in the population. LCSH decided to allow some alteration of terms in 1996 to better reflect the needs and access of library users. Nevertheless, many common terms, or ‘natural language’ terms are not used in LCSH, and may in effect limit the ability for users to locate items. There is a vibrant, interesting and growing tradition of research in Library and Information Science faculties about the cultural and gender biases that affect the terms used in LCSH, which in turn may limit or deprive library users access to information stored and disseminated in collections. A notable American Library Science scholar on this subject is Sanford Berman. Using LCSH The Subject Headings are published in large red volumes (currently five), which are typically displayed in the reference sections of research libraries. They may also be searched online in the Library of Congress Classification Web</ref> Library of Congress Classification Web , Library of Congress.

Retrieved April 4, 2008.</ref> a subscription service, or free of charge at Library of Congress Authorities [1] The Library of Congress issues weekly updates. Once a library user has found the right subject heading they are an excellent resource for finding relevant material in your library catalogue. Increasingly the use of hyperlinked , web-based Online Public Access Catalogues, or OPACs, allow users to hyperlink to a list of similar items displayed by LCSH once one item of interest is located. However, because LCSH are not necessarily expressed in natural language, many users may chose to search OPACs by keywords. Moreover, users unfamiliar with OPAC searching and LCSH, may incorrectly assume their library has no items on their desired topic, if they chose to search by ‘subject’ field, and the terms they entered do not strictly conform to a LCSH. For example ‘body temperature regulation’ is used in place of ‘thermoregulation’. Thus the easiest way to find and use LCSH is to start with a ‘keyword’ search and then look at the Subject Headings of a relevant item to locate other related material. Conclusion Despite their limitations, LCSH are widely used in library catalogs in North America and around the world.

They should not be confused with the Library of Congress Classification, which does not attempt to evaluate the subject content of items, but rather broadly categorizes the item in a subject hierarchy. Many libraries, especially public and school libraries will use the Dewey Decimal Classification system for organizing collections, but will employ LCSH for accessing material by topic. Dewey Decimal Classification System The Dewey Decimal Classification (DDC, also called the Dewey Decimal System) is a proprietary system of library classification developed by Melvil Dewey in 1876, and has since then been greatly modified and expanded through 22 major revisions, the most recent in 2004. How it works The DDC attempts to organize all knowledge into ten main classes. The ten main classes are then further subdivided. Each main class has ten divisions, and each division has ten sections. Hence the system can be summarized in 10 main classes, 100 divisions and 1,000 sections. DDC's advantage in choosing decimals for its categories allows it to be both purely numerical and infinitely hierarchical.

It also uses some aspects of a faceted classification scheme, combining elements from different parts of the structure to construct a number representing the subject content (often combining two subject elements with linking numbers and geographical and temporal elements) and form of an item rather than drawing upon a list containing each class and its meaning. Except for general works and fiction , works are classified principally by subject, with extensions for subject relationships, place, time or type of material, producing classification numbers of not less than three digits but otherwise of indeterminate length with a decimal point before the fourth digit, where present (e.g. 330 for economics + 9 for geographic treatment + 4 for Europe = 330.94 European economy; 973 for United States + 05 form division for periodicals = 973.05, periodicals concerning the United States generally). Books are placed on the shelf in increasing numerical order; the whole number to the left of the decimal is in counting order, while the digits to the right of the decimal are compared one digit at a time, with a blank coming before zero.

(Example: 050, 220, 330.973, 331 etc.) When two books have the same subject, and therefore the same classification number, the second line of the call number, which usually has the first letter or first several letters of the author's last name (or the title if there is no identifiable author), is placed in alphabetical order. It is a common misconception that all books in the DDC are non-fiction. The DDC has a number for all books, including those that generally become their own section of fiction. If DDC rules are strictly followed, American fiction is classified in 813. Most libraries create a separate fiction section to allow shelving fiction in a more generalised fashion than Dewey provides for, or to avoid the space that would be taken up in the 800s. DDC compared to other classification systems DDC's numbers formed the basis of the more expressive but complex Universal Decimal Classification, which combines the basic Dewey numbers with selected punctuation marks (comma, colon, parentheses etc.). Besides its frequent revision, DDC's main advantage over its chief rival—the Library of Congress Classification system developed shortly afterward—is its simplicity.

Thanks to the use of pure notation, a mnemonics system and a hierarchical decimal place system, it is generally easier to use for most users. DDC and UDC are also more flexible than Library of Congress Classification because of greater use of facets (via auxiliary tables) while Library of Congress Classification is almost totally enumerative. On the flip side, DDC's decimal system means that it is less hospitable to the addition of new subjects, as opposed to Library of Congress Classification which has 21 classes at the top level. Another side effect of this is that DDC notations can be very much longer compared to the equivalent class in other classification systems. Another disadvantage of DDC is that it was developed in the nineteenth century, by essentially one man, and was built on a top down approach to classify all human knowledge which made it difficult to adapt to changing fields of knowledge. In contrast, the Library of Congress Classification system was developed based mainly on the idea of literary warrant; classes were added (by individual experts in each area) only when needed for works owned by the Library of Congress.

As a result, while the Library of Congress Classification system was able to incorporate changes and additions of new branches of knowledge, particularly in the fields of engineering and computer science (the greater hospitality of the Library of Congress Classification was also a factor), DDC has been criticized for being inadequate for covering those areas. As a result, most major academic libraries in the US do not use the DDC because the classification of works in those areas is not specific enough. The Library of Congress Classification system is not without problems; because each area is developed by an expert according to demands of cataloging, there is little consistency. It is also highly US-centric (more so than DDC) because of the nature of the system, and compared to DDC and UDC it has been translated into far fewer languages. Ownership and administration The Online Computer Library Center of Dublin, Ohio, acquired the trademark and any copyrights associated with the Dewey Decimal System when it bought Forest Press in 1988. OCLC maintains the classification system and publishes new editions of the system.

The work of assigning a DDC number to each newly published book is performed by a division of the Library of Congress, whose recommended assignments are either accepted or rejected by the OCLC after review by an advisory board; to date all have been accepted. In September 2003, the OCLC sued the Library Hotel for trademark infringement. The settlement was that the OCLC would allow the Library Hotel to use the system in its hotel and marketing. In exchange, the Hotel would acknowledge the Center's ownership of the trademark and make a donation to a nonprofit organization promoting reading and literacy among children. Classes The system is made up of ten main classes or categories, each divided into ten secondary classes or subcategories, each having ten subdivisions of its own. For a more detailed list, see List of Dewey Decimal classes. ↑ Library of Congress Authorities , Library of Congress. Retrieved April 4, 2008. References Buchanan, Brian. Theory of Library Classification. Outlines of modern librarianship. London: C. Bingley, 1979.

ISBN 0851572707 ISBN 9780851572703 Dewey, Melvil, et al. Dewey Decimal Classification and Relative Index. Albany, New York: Forest Press, a division of OCLC Online Computer Library Center, 1989. ISBN 0910608377 ISBN 9780910608374 LaMontagne, Leo E. American Library Classification: With Special Reference to the Library of Congress. Hamden, Conn: Shoe String Press, 1961. Library of Congress. Library of Congress Classification. T. Technology. Washington, D.C.: Library of Congress, Cataloging Distribution Service, 2007. ISBN 0844411647 ISBN 9780844411644 Library of Congress. Library of Congress Subject Headings. Washington: Library of Congress, 1975. Library of Congress. Subject Cataloging Manual. Classification. Washington, D.C.: Cataloging Distribution Service, Library of Congress, 1992. World Council of Churches. Library Classification.

Geneva: WCC Library, 1971. Wynar, Bohdan S., Arlene G. Taylor, and Jeanne Osborn. Introduction to Cataloging and Classification. Library science text series. Littleton, Colo: Libraries Unlimited, 1980. ISBN 0872872203 ISBN 9780872872202 ISBN 0872872211 ISBN 9780872872219 External links Dewey Decimal classification - WikiEducator Dewey Decimal classification 4 Number Building Library Classification Librarianship involves the selection, acquisition, organization and dissemination of information and knowledge available in various forms. The information available is immense and increasing, but not necessarily usable. In order to make the information retrievable and usable, the various sources of information need to be organized in a library. The larger the number of unorganized library holdings, more difficult to locate the needed document. Librarians address this issue with the help of classification. According to Dr.

Ranganathan, Library Classification is "the translation of the name of the subject of a book into preferred artificial language of ordinal numbers, which represent some features of the books other than their thought content”. In succinct, a library classification is a system of coding and organizing library materials (books, serials, audiovisual materials, computer files, maps, manuscripts, realia) according to their subject and allocating a call number to each information resource. The aim of Library Classification is to arrange the documents in the most helpful sequence. Libraries adopted different practices to organize their collections. Some shelved materials by when the items arrived in the library. Others organized their collections by size or color of the book. Few others organized by author, by title, and/or by subject. Among all the arrangements, organizing library collections according to subject found helpful to users. Subject arrangement on the shelves is more convenient to users since items on the same subject are collated together. However, this subject arrangement should be based on sound principles and established plans and systems that can be consulted by Library and Information Service professionals for intellectual organization of information. Consequently, various classification systems have been devised to serve as the reference tools for organizing information, thereby, facilitating easy access and retrieval.

Classification Schemes A classification system (scheme) as an established information processing and retrieval tool divides the “universe of knowledge” into various categories and subcategories in a hierarchical manner. Each category represents a class and each subcategory a division and/or subdivision. The division of knowledge proceeds from general classes to more and more specific subdivisions. In a classification scheme each class and subdivision is assigned with a specific symbol (class number), so as to assure that documents on the same subject are always classified under that symbol. Symbols used are numbers, letters, or a combination of letters and numbers, which may vary with the classification system used. The Dewey Decimal Classification is a numeric ordering system, whereas the Colon Classification is an alphanumeric system. According to Margaret Mann, “a system for classification of books is a schedule, which maps out the field of knowledge in ways that are suitable for library purposes; main classes are followed by divisions and subdivisions of these classes; are gradation of subject is so arranged that specific subjects grow out of general subjects”. According to SR Ranganathan, classification scheme is “a scheme of classes fitted with terminology and notation”.

A library classification system aids a classifier in ordering of the universe of knowledge such that books of similar subjects can be kept together on the shelves, assigning a unique shelf address (call number) to each document procured. Classification systems are designed to give a numerical, or alphanumerical notation to each item in the library. This notation is designed to indicate the subject matter of the item being classified. The first practical universal classification schemes were developed in the late-nineteenth-century as a response to the problem of organizing libraries in the context of rapidly growing knowledge and an increase in the numbers of printed books. Universal schemes aim to be both comprehensive and also to expand and contract to fit the state of knowledge at any time. The most widely used universal classification schemes are the Dewey Decimal Classification (DDC), the Colon Classification (CC) the Universal Decimal Classification (UDC) and the classification scheme devised by the Library of Congress (LCC). Dewey Decimal Classification DDC is the most widely used classification system in the world. DDC is a general knowledge organization tool that is continuously revised to keep pace with knowledge. It provides a logical system for organizing every item in a library’s collection.

Melvil Dewey conceived Dewey Decimal Classification system (DDC) in 1873, which was first published in 1876. Editions and Formats Now in its 22nd edition, DDC is available in print and Web versions. Dewey is also used for other purposes, example as a browsing mechanism for resources on the Web. The DDC has been translated into more than thirty languages. Translations of the latest full and abridged editions of the DDC are completed, planned, or underway in Arabic, Chinese, French, German, Greek, Hebrew, Icelandic, Italian, Korean, Norwegian, Russian, Spanish and Vietnamese. First Edition The first edition of DDC was published anonymously in 1876 under the title "A Classification and Subject Index for Cataloguing and Arranging the Books and Pamphlets of a Library". It comprised of 42 pages, among which 11 pages were schedules and 18 pages were index. It included schedules to 1,000 divisions numbered 000–999, together with a relative index and prefatory matter.

The major significance of this edition was that it was simple to work with and provided systematic arrangement of the materials in a library on the basis of subject approach. Second Edition The second, revised and greatly enlarged edition was published under Dewey’s name in 1885. The second edition entitled, “Decimal Classification and Relative Index,” appeared in 1885. This was eleven times voluminous than the first edition. It contained many changes. Since then 20 full editions and 14 abridgments have appeared. The 21st edition of the DDC and Dewey for Windows published in 1996, making it the first time print and electronic formats are published simultaneously. It displayed the continuous revitalization efforts that have kept it contemporary throughout the twentieth century. Progress in science, technology, and even thought and culture was consistently reflected within the classification. In 2002, WebDewey and Abridged WebDewey were published. DDC22 published in mid-2003, includes many new features that make the classification easier to use.

DDC22 is the culmination of the work of editors, the Decimal Classification Editorial Policy Committee (EPC), and many advisors representing various fields and specific constituencies. Edition 22 reflects current thought in knowledge organization, and incorporates updates and changes identified during the use of 21st edition. Edition 22 The 22nd edition reflects improvements in terminology in geographic area, law, political parties, language, literature and historical periods. Two striking changes in Edition 22, the removal of Table 7 and the streamlining of the Manual, have been motivated by a desire to promote classifier efficiency. Table 7 is removed and replaced with direct use of notation already available in the schedules and in notation 08 from Table 1. Information easily accommodated in notes in the tables and schedules has been transferred from the Manual, and redundant information already in the schedules and tables has been eliminated from the Manual. The remaining Manual entries are revised in a consistent style to promote quick understanding and efficient use. The print version of the DDC 22 consists of the following four volumes: Volume 1 comprises of introductory matter, the manual, auxiliary tables, and lists of relocations, discontinuations and reused numbers etc.

Volume 2 enumerates the 3 summaries and embeds the hierarchical notations from 000–599. Volume 3 embeds the notations 600–999 to organize knowledge related to technology, arts, literature and geography. Volume 4, the relative index lists the concepts alphabetically. WebDewey Web Dewey gives access to an enhanced version of the DDC22 database on the Web. WebDewey is part of the OCLC suite of cataloguing and metadata services. WebDewey offers easy-to-use, World Wide Web-based access to the Dewey Decimal Classification (DDC) and related information, with searching and browsing capabilities; Library of Congress Subject Headings (LCSH) intellectually and statistically mapped to Dewey numbers; and links from the mapped LCSH to the corresponding LCSH authority records. WebDewey and Abridged WebDewey, the electronic versions of the full and abridged editions, respectively, are updated frequently and contain additional index entries and mapped vocabulary. The electronic versions and supplemental Web postings are the chief sources of ongoing updates to the DDC.

On OCLC’s Dewey Website , selected new numbers and changes to the DDC are posted monthly, and mappings between selected new Library of Congress Subject Headings (LCSH) and Dewey numbers are posted biweekly. Structure In DDC, basic classes are organized by disciplines or fields of study. At the broadest level, the DDC is divided into ten main classes, which together cover the entire world of knowledge. Each main class is further divided into ten divisions, and each division into ten sections (not all the numbers for the divisions and sections have been used). DDC Summaries The main structure of the DDC is presented in the DDC Summaries following the introduction. DDC22 provides three summaries, showing successively the 10 main classes (first summary), the 100 divisions (second summary), and the 1,000 sections (third summary) of the basic scheme. Each class consists of a group of related disciplines. First Summary - Ten Main Classes The first summary contains the ten main classes. The first digit in each three-digit number represents the main class.

The ten main classes are: 000 Computer Science, information & general works 100 Philosophy & psychology 200 Religion 300 Social Sciences 400 Languages 500 Science 600 Technology 700 Arts & recreation 800 Literature 900 History & geography Class 000 is the most general class, and is used for works not limited to any one specific discipline, example, encyclopedias, newspapers, general periodicals. This class is also used for certain specialized disciplines that deal with knowledge and information, example, computer science, library and information science, journalism. Each of the other main classes (100-900) comprises a major discipline or group of related disciplines. Class 100 covers philosophy, paranormal phenomena, and psychology. Class 200 is devoted to religion. Both philosophy and religion deal with the ultimate nature of existence and relationships, but religion treats these topics within the context of revelation, deity, and worship. Class 300 covers the social sciences.

Class 300 includes sociology, anthropology, statistics, political science, economics, law, public administration, social problems and services, education, commerce, communications, transportation, and customs. Class 400 comprises language, linguistics, and specific languages. Literature, which is arranged by language, is found in 800. Class 500 is devoted to natural sciences and mathematics. Natural sciences (500) describe and attempt to explain the world in which we live. Class 600 is technology. Technology consists of utilizing the sciences to harness the natural world and its resources for the benefits of humankind. Class 700 covers the arts: art in general, fine and decorative arts, music, and performing arts. Recreation, including sports and games, is also classed in 700. Class 800 covers literature, and includes rhetoric, prose, poetry, drama, etc. Folk literature is classed with customs in 300. Class 900 is devoted to history and geography. When a work is a story of events that have transpired or an account of existing conditions in a particular place or region, it is classed in 900.

A history of a specific subject is classed with the subject. There are ten and only ten main classes in DDC. There is no change in the number ever since the publication of the first edition of the scheme. Each of the classes has ten divisions. These divisions are further divided − and then further divided. Each division becomes more specific. The more the numbers, the more specific the subject is. In this way, the Dewey classification system progresses from the general to the specific. The decimal place is used to make the number even more specific. Second Summary – Hundred Divisions Each of the main class in the First Summary is further divided into 10 divisions. Thus, the second summary contains the hundred divisions. The second digit in each three-digit number indicates the division. For example, 600 is used for general works on technology, 610 for medicine and health, 620 for engineering, 630 for agriculture. Let us take the main class 700 Fine Arts and its second summary (10 x 10) 100 divisions. Each division is also represented by three digited numbers, wherein the last digit is always a zero, which indicates the absence of a section.

700 Fine Arts 710 Civic and landscape art 720 Architecture 730 Sculpture 740 Drawing, decorative arts 750 Painting 760 Graphic arts 770 Photography 780 Music 790 Recreational and performing arts - cinema, theatre, indoor games, sports. The numbers of the divisions are to be treated as 'decimal numbers' as in the case of the main classes. We should presume that there is a dot before each number. For example, 790 should be spelt as seven, nine, zero but not as five hundred ninety. Third Summary – Thousand Sections Each of the 100 divisions is separated again into 10 sections. Thus, the third summary contains the thousand sections. Let us take the division 790 – Recreational activities in general. The section number is also a three digited one, wherein all are substantive digits. 790 Recreational activities in general 791 Entertainment – circuses, cinema, radio, television 792 Theatre 793 Indoor games, puzzles, dancing etc.

794 Indoor games of skill – chess, snooker 795 Games of change, card games 796 Ball games, athletics, walking, climbing, combat sports, ice and snow sports 797 Aquatic and air sports – boating, swimming, gliding, sky diving 798 Horsemanship and horse racing 799 Fishing, hunting, shooting. The numbers of the sections are also to be treated as ‘decimal numbers’ as in the case of main classes and divisions. Hence, the number 799 should be spelt as seven nine nine. Notation A basic principle of DDC is it is arranged by discipline and not by subject; notation used is the pure notation and structural and notational hierarchy are maintained throughout the schedules. Indo-Arabic numerals are used to represent the class numbers. The first digit in each three-digit number represents the main class. The second digit in each three-digit number indicates the division. The third digit in each three-digit number indicates the section. The DDC uses the convention that no number should have fewer than three digits; zeros are used to fill out numbers.

The notation of DDC schedule is made up of three basic numbers, which represent a particular place in the schedules. The first digit indicates one of the ten main classes. The second digit represents one of the ten divisions within the class. The third digit distinguishes one of the ten sections. Most notations require further refinements, so a decimal is inserted following this three-part number to be followed by more digits representing a specific element of the topic. The notation of a class varies with the depth of the discipline. If the extension of a discipline is more, the class number will be short. If the intention is more, the class number will be long. Decimal Fractions All the decimal fractions follow a whole number preceded by a decimal point, as an indicator. For example in 10.5, read as ten point five, 5 is a decimal fraction and is preceded by a decimal point. Similarly 0.92 is read as zero point nine two or simply as decimal nine two. The decimal fractions have constant place value of the digits. If we add any digit to the right end of any decimal fraction, the place value of the already present figures does not change.

For example, if a decimal fraction 52 is extended by 5 to make it 525, the original place value of the first two digits, viz., 52 remains unaltered. This is due to the fact that every digit in a decimal fraction has its fixed absolute value irrespective of the total number of digits in a decimal sum. This property is the reverse of what it is in the whole numbers. In any classification system the number or symbols used to denote subjects have only ordinal value. They do not possess any cardinal value. The digits used in DDC are also devoid of any measure or weight or power or quantity. They only indicate their sequential value, that is, which number is to come earlier and which later. In DDC, of the two subjects denoted by numbers, say 935 and 954, it never means that the later is of any more value or importance than the former or vice versa. It only indicates that on the library shelves the book bearing the class number 954 will come after that of 953 and so on.

When 511 will come earlier than 512 on the shelves, it does not indicate any of less value than 512 and by the same rule, 45 will come earlier than 5 and 301 earlier than 92 on the shelves. Use of Decimal Point A decimal point or dot is inserted between the third and fourth digits of the complete number. The dot is not a decimal point in the mathematical sense, but a psychological pause to break the monotony of numerical digits and to ease the transcription and copying of the class number. Educational psychologists believe that 324.12 is more easily remembered than 32412. Hence, this dot has no function other than to reinforce memory. Relative Index The “relative” index is so called because it is claimed to show relationships of each specific topic to one or more disciplines and to other topics. It contains terms found in the schedules and tables, and synonyms for those terms; names of countries, states, provinces, major cities, and important geographic features; and some names of persons. The DDC relative index enumerates alphabetically all the main headings in the classification schedules, plus certain other specific entries not actually listed in the schedules.

The classifier should consult the index, especially in cases in which the location of the desired topic, or the precise nature of its relation to other topics, is in doubt. Yet the relative index should never become a substitute for the schedules. Since the primary arrangement of knowledge is by discipline, any specific topic may appear in any number of disciplines. Various aspects of such a topic are usually brought together in the relative index. Notes Notes supply information that is not obvious in the notational hierarchy or in the heading with regard to order, structure, subordination, and other matters. Notes may appear in the record for a number or a span of numbers. Notes may also appear at the beginning of a table. Footnotes are used for instructions that apply to multiple subdivisions of a class, or to a topic within a class. Individual entries in the Manual are also considered notes. Notes in the schedules and tables generally appear in the following order: revision, former-heading, definition, number-built, standard-subdivisions-are added, variant-name, scope, including, class-here, arrange, add (including subdivisions-are-added), build, preference, discontinued, relocation, class-elsewhere, see-reference, see-also reference, see-Manual, and option notes.

All these types of notes can be grouped in 3 categories: Notes that describe what is found in a class; Including notes (notes that identify topics in standing room); and Notes that describe what is found in other classes; (iv) Notes that explain changes or irregularities in the Schedules and Tables. Tables Auxiliary tables 1 through 6, found in volume 1 of DDC22, give the classifier one way to expand existing numbers in the schedules. Each number in these tables is preceded by a dash to show that it cannot stand alone as a classification number i.e., never used as a class number but attached to the class numbers (000–999) taken from the schedule. The dash should be omitted when the number is attached to a class notation.

The tables in the DDC 22 are: Table 1 : Standard subdivisions Table 2 : Geographic Areas, Historical periods, Persons Table 3 : Subdivision for the Arts, for Individual Literature, for Specific Literary Forms T3A Subdivisions for Works by or about Individual Authors T3B Subdivisions for Works by or about More than One Author T3C Notation to Be Added Where Instructed in Table 3B, 700.4, 791.4, 808 -809 Table 4 : Subdivision of Individual Language and Language Families Table 5 : Ethnic and National groups Table 6 : Languages. Table numbers are given in full in the number column of the tables, and are never used alone. Except for notation from Table 1 (which may be added to any number unless there is an instruction in the schedules or tables to the contrary), notations from the tables are added only as instructed in the schedules and tables. Number building with the aid of notations from the Tables is discussed in detail in the subsequent chapters. Number Building

Question: Dewey Decimal Classification, Universal Decimal Classification and Library of Congress Classification are three methods of coding and organizing what?
Answer: Library materials